Abstract: At approximately 7:30 a.m. on July 23, 1999, Employees #1 and #2, both iron workers, were on the third floor waiting for a load of "stirrups" (re-bar sections) to be landed. The bundle came through a wall opening, and they landed the load onto a cart. They repositioned the stirrups in the cart and, within a minute, one end of the floor dropped to the second floor, at an angle. The cart with the stirrups pinned Employee #1 against the wall, and he suffered a fractured right cheek and facial lacerations. Employee #2 was lodged next to the wall opening and suffered a contusion of his right thigh. They were taken to San Francisco General Hospital.